Optimization Based Decoupling Control for Alstom Coal Gasification Process

This paper presents an optimization based approach to design decouplers for multi-variable systems by reducing interactions through an explicit minimization of the off-diagonal terms of an effective relative gain array (ERGA). The ERGA method is an interaction assessment method which considers the dynamic interactions between the variables. Hence ERGA is chosen over the relative gain array(RGA) approach which uses only steady state information, and dynamic RGA methods, which are often computationally rigorous. The proposed technique is applied to Alstom benchmark challenge-I and decoupler matrices are estimated at three different loading points of the coal gasifier using the above optimization approach. Closed loop responses based on the decoupled multiloop configuration for the Alstom gasifier problem gave satisfactory responses and point to the efficacy of the proposed method.